Abstract

In this study, a two-stage filter structure is introduced for speech enhancement. The first stage is an adjustable filter and sum beam-former with four-microphone array. The control of beam-forming filter is realized by adjusting only a single control variable. Different from the adaptive beam-forming filter, the proposed filter structure does not bring to any adaptive error noise, thus, it also does not bring the trouble to the second stage of the speech signal processing. The second stage of the proposed filter is a Wiener filter. The estimation of signal’s power spectrum for Wiener filter is realized by cross-correlation between primary outputs of two adjacent directional beams. This estimation is based on the assumption that the noise outputs of the two adjacent directional beams come from two independent noise source but the speech outputs come from the same speech source. The simulation results shown that the proposed algorithm can improve the Signal-Noise-Ratio (SNR) about 6 dB.

Keywords:

Adjustable filter, beam forming, post wiener filter, speech enhancement,

References

Competing interests

The authors have no competing interests.

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Copyright

The authors have no competing interests.